Conventionally, an electric automobile as described in Patent Literature 1 is known as an electric vehicle equipped with an automatic transmission as described above.
The electric automobile includes an electric motor solely as a power source and the automatic transmission disposed between the electric motor and driving wheels, and allows the automatic transmission to convert motor torque from the electric motor and transmit the thus converted motor torque toward the driving wheels.
In the automatic transmission, shift from a gear stage (shift stage) as selected to a target gear stage is performed by changeover of transmission friction elements between engagement and release.
Upon carrying out the changeover of transmission friction elements between engagement and release during the shift operation, a predetermined time (shift time) is necessary from start of the shift operation to finish of the shift operation for such a reason that it is required to carry out changeover between a release-side transmission friction element to be switched from an engagement state to a release state and an engagement-side transmission friction element to be switched from a release state to an engagement state.
On the other hand, since a large torque is required upon depressing an accelerator pedal, the automatic transmission is downshifted (kick-down shifted) to a low-side gear ratio. Also, during a shift time in which the downshift is executed, it is necessary to transmit a large torque responding to depression of the accelerator pedal toward the driving wheels.
Further, generally, upon controlling the electric motor, a target motor torque requested by a vehicle driver is determined from motor rotation speed and an amount of depression of an accelerator pedal, and the electric motor is controlled such that the motor torque reaches the target value.